The world was their laboratory: how two pioneer scientist-administrators, James Watt and Zdenek Fejfar, advanced methods and international collaboration in cardiovascular disease epidemiology during the Cold War.

In 1952, James Watt, a young US Public Health Service (PHS) infectious disease epidemiologist, was appointed-amid wide surprise-director of the US National Heart Institute (NHI) where he served until 1961. He skillfully advanced epidemiologic research methods and study conduct nationally while also establishing epidemiology in the administrative hierarchy of the institute. Watt soon turned to development of an effective program in international cardiovascular disease (CVD) epidemiology under auspices of the World Health Organization (WHO) at the United Nations in Geneva. That effort resulted in the 1959 appointment of Zdenek Fejfar, a young Czech clinical investigator, as director of the WHO CVD Unit. The coming together of Watt and Fejfar, with a joint focus on improved methods and population comparisons, helped establish a vigorous international community of CVD epidemiology. Their collaboration and friendship remained active and close throughout their career assignments and thereafter, as documented in this story.